Dynamic modeling of a SI/HCCI free-piston engine generator with electric mechanical valves

► A dynamic physics-based model for FPEG is developed for control synthesis and design. ► The model includes piston motion, gas filling dynamics, combustion and generator. ► Successful mode transition requires proper scheduling of the system inputs. ► Scavenging is key for trapped mass balance and thus compression ratio regulation. ► The electric mechanical valves (EMVs) enable optimization of the scavenging process.